
\begin{tikzpicture}
  \tkzDefPoints{0/0/A,2/{2*sqrt(3)}/B,{3*sqrt(3)}/0/C,2/0/H}
  \tkzDrawPolygon(A,B,C)
  \tkzDrawSegment(B,H)
  \tkzMarkRightAngle(C,H,B)
  \tkzDrawPoints(A,B,C,H)
  \tkzLabelPoints[below](A,C,H)
  \tkzLabelPoints[above](B)
\end{tikzpicture}
